Transcript Domain V Evolution

Domain V
Evolution
Origins of Evolution
Jean Baptiste de Lamarck and
Acquired Characteristics
 Charles Darwin




Charles Lyell’s Principles of Geology
Thomas Malthus called The Principles of
Population
40,000-mile trip on the Beagle
Galapagos Islands

What did he find there?
 Aquatic iguanas
Giant Tortoises
 Species of finches

2 Themes Emerged


Variations within a species were
dependent on the environment.
Organisms on the Galapagos
Islands had become
geographically separated
resulting in reproductive
isolation which leads to
speciation.
Natural Selection

Changes in a population that
occur when organisms with
favorable variations for that
particular environment
survive, reproduce and pass
these variations on to the
next generation.
Darwin’s Theory
Decent with modification
through natural selection.
 Environmental Challenges
result in certain traits
increasing the reproductive
fitness of certain individuals
within a species.

History of Life

Types of Evolution
Divergent (Adaptive Radiation)
 Convergent

•Rates of Evolution
•Gradualism
•Punctuated Equilibrium
Types of Natural
Selection
Stabilizing Selection
 Directional Selection
 Diversifying Selection
 Disruptive Selection
 Balancing Selection


Diversifying Selection
When a population is faced
with conditions so diverse
that no single phenotype is
more successful that any
other, genetic and phenotypic
variability allow different
selective pressures to
operate at the same time.
Balancing Selection operates
to counteract the loss of
variant alleles in a
population.
 Two forms of : heterozygote
advantage and frequencydependent selection.

Biodiversity

Resulted from divergent
evolution.
Lines of Evidence
Incomplete Fossil Record
>Relative Dating
>Time Averaging
>Radioisotope Dating
 Building a Phylogeny
>Phylogenetic Tree

Mass Extinctions

Were catastrophic events the
cause of mass extinctions, did
they happen quickly or did
they occur over a long period
of time?

If they occurred over a
long period of time, why
did the species not adapt
to their changing
environment in order to
survive?
Biological
Resistance
Oysters in Malpeque Bay
 Insect Resistance to
Insecticides
 Viruses
 Gene Amplification
